Johnson Controls York YHAU-C, Installation, Operation And Maintenance Manual

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Figure 68: Location of manual valve in purge system
V11 Purging operating valve for purge tank line
V16 Purging operating valve for absorber line
V14 Purge main valve
Manual method to purge air directly from absorber
When the chiller operates at a lower capacity than usual for a long period of time or when it restarts
after a power failure, the absorber can contain non-condensable gases. If the machine starts under
these conditions, its performance and efficiency go down. If this happens, purge non-condensable
gas directly from the absorber manually according to the following procedure.
1. Set the valves according to pattern B shown in Figure 69.
2. Press the Purge Mode Manual button.
3. Press the Manual Purge ON button. The vacuum pump starts. The solenoid valves SV1 and SV2
open.
4. After step 3 begins, confirm that vacuum gauge stands at 0 ~ 0.15 psi.
5. Reading the vacuum gauge, open valve V13.
6. Open valve V16 gradually. Confirm that the pressure on the vacuum gauge increases slightly.
Note: If the pressure decreases when valve V16 opens, the vacuum pump capacity is too
small. Close valve V16 at once. See Troubleshooting performance issues and check the
purge line.
7. If no problems are found, open valve V16 the rest of the way.
145 YHAU-C Single Effect Steam-Fired Absorption Chiller